1. Field of the Disclosure
The present disclosure relates to an ice-making machine, and more particularly, to a generation of an acoustic wave, and an analysis of the acoustic wave as it is propagating through a body of water in the ice-making machine. The analysis recognizes when the body of water is frozen, so that the body of water can be harvested, as ice, from the ice-making machine.
2. Description of the Related Art
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, the approaches described in this section may not be prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
For efficient operation of an ice-making machine, it is desirable to remove the ice, also known as harvesting the ice, soon after the ice has fully formed. Such harvesting of the ice allows fora new body of water to be introduced so that a new body of ice can be formed, thus maximizing the usage of the ice-making machine.
In the current state-of-the-art, several methods are used to sense when an ice-making machine evaporator is ready and “loaded” with sufficient ice for collection or “harvest”. Some methods employed to sense a presence of ice use micro-switch, capacitance, optical, or microphone-based technologies to detect a thickness of an ice-bridge between individual cubes of ice, while the ice is forming on an evaporator. Each of these methods suffer from a common drawback of “non-deterministic ice formation”. Ice-maker water is pumped up and over the evaporator, and then allowed to fall, in a waterfall-like cascade, over a cooled evaporator into a collection trough sitting at the bottom of the water path. Because gravity and environmental vibration create “noise”, these “water-ribbons” trace down the evaporator and freeze in random paths. Therefore, there are ordinarily no two ice-making cycles with the same ice formation pattern. Thus, it becomes difficult to determine at what point in the ice-making cycle enough ice has been built up on the evaporator to trigger the removal and collection, i.e., harvest, of that slab of ice. This leads to a problem of double-slabbing and an eventual freeze-up of the ice-maker, which further results in a need for thawing and/or service of the ice-making machine. This dilemma can be even more compounded by the fact that some operators prefer either thicker or thinner cubes of ice based on their application need, and can set a specific ice-bridge thickness for their ice-making machine.
Another technique for recognizing the readiness of the ice for harvesting is to monitor a magnitude of a mechanical vibration that is propagating through a body of water as the body of water is being frozen. At a point in time when the magnitude exceeds a predetermined threshold, the body of water is assumed to be adequately frozen, and so, is harvested. A possible drawback of this technique is that it does not distinguish between various possible sources of mechanical vibrations, and so, cannot determine whether the change is due to a change in acoustics of the ice-making machine or spurious acoustics in an ambient noise environment. Consequently, this technique does not necessarily initiate harvesting at a most optimum time, and therefore, the ice-making machine may be operating at a less than optimum level of efficiency.
It is an object of the present disclosure to provide a technique for harvesting ice in an ice-making machine at a time that optimizes the efficiency of the ice-making machine.